[PATCH v2 15/23] PCI: aardvark: Optimize writing PCI_EXP_RTCTL_PMEIE and PCI_EXP_RTSTA_PME on emulated bridge
Marek Behún
kabel at kernel.org
Sun Jan 9 17:50:10 PST 2022
From: Pali Rohár <pali at kernel.org>
To optimize advk_pci_bridge_emul_pcie_conf_write() code, touch
PCIE_ISR0_REG and PCIE_ISR0_MASK_REG registers only when it is really
needed, when processing PCI_EXP_RTCTL_PMEIE and PCI_EXP_RTSTA_PME bits.
Signed-off-by: Pali Rohár <pali at kernel.org>
Signed-off-by: Marek Behún <kabel at kernel.org>
---
drivers/pci/controller/pci-aardvark.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)
diff --git a/drivers/pci/controller/pci-aardvark.c b/drivers/pci/controller/pci-aardvark.c
index 8706a5f58eb5..e7b9ca31c79c 100644
--- a/drivers/pci/controller/pci-aardvark.c
+++ b/drivers/pci/controller/pci-aardvark.c
@@ -934,19 +934,21 @@ advk_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,
advk_pcie_wait_for_retrain(pcie);
break;
- case PCI_EXP_RTCTL: {
+ case PCI_EXP_RTCTL:
/* Only mask/unmask PME interrupt */
- u32 val = advk_readl(pcie, PCIE_ISR0_MASK_REG) &
- ~PCIE_MSG_PM_PME_MASK;
- if ((new & PCI_EXP_RTCTL_PMEIE) == 0)
- val |= PCIE_MSG_PM_PME_MASK;
- advk_writel(pcie, val, PCIE_ISR0_MASK_REG);
+ if (mask & PCI_EXP_RTCTL_PMEIE) {
+ u32 val = advk_readl(pcie, PCIE_ISR0_MASK_REG);
+ if (new & PCI_EXP_RTCTL_PMEIE)
+ val &= ~PCIE_MSG_PM_PME_MASK;
+ else
+ val |= PCIE_MSG_PM_PME_MASK;
+ advk_writel(pcie, val, PCIE_ISR0_MASK_REG);
+ }
break;
- }
case PCI_EXP_RTSTA:
- new = (new & PCI_EXP_RTSTA_PME) >> 9;
- advk_writel(pcie, new, PCIE_ISR0_REG);
+ if (new & PCI_EXP_RTSTA_PME)
+ advk_writel(pcie, PCIE_MSG_PM_PME_MASK, PCIE_ISR0_REG);
break;
case PCI_EXP_DEVCTL:
--
2.34.1
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